In Search Of Stem Cells
Tv crews camped out, reporters swarmed, phones rang off the hook--and employees at the year-old biotech firm CyThera, Inc., felt so besieged that they took its name off the door. The sudden attention followed the announcement by the National Institutes of Health last week that CyThera has more stem-cell colonies--nine--than anyone else in the United States. Fear that it would be targeted by anti-stem-cell activists (Operation Rescue vows to picket) was just the beginning of CyThera's woes. The obscure La Jolla, Calif., company, with only 12 employees, isn't even ready to analyze its stem-cell lines to see whether they're what researchers need, let alone supply biologists itching to get their hands on them. Warns chief scientist Lutz Giebel, "The cells are not ready to be released"--and won't be for at least a year.
When President George W. Bush announced last month that there were scores of stem-cell colonies around the world that federally funded scientists would be allowed to study, biologists were skeptical: just where the heck were all these cells? Last week NIH finally coughed up the answer. Ten universities, research centers and companies control 64 human stem-cell lines, derived from 64 blastocysts (days-old embryos). But dozens of those colonies belong to firms that, like CyThera, are so small that making the cells available to all comers would swamp them. "We've already had about 20 inquiries," says CEO John Smeaton of BresaGen, Inc., in Athens, Ga. "I think we're in a position to supply one or two, but if hundreds of labs want our cells, we'll be overwhelmed." And because stem cells can be temperamental--when BresaGen got some for its lab in Australia, the cells refused to grow--shipping them to researchers requires more than some dry ice and a call to FedEx. Scientists who want cells from BresaGen's four colonies might have to spend days at its lab learning to nurture them, taxing its 17 employees. "A sudden demand," says BresaGen's chief scientist, Allan Robins, "will be hard to meet."
In addition, dozens of the 64 colonies may lack the magical quality that makes stem cells such a hot property in the first place. Called pluripotency, it's the ability to morph into any of the 200-plus kinds of human cells. Despite NIH's claim that all 64 colonies "show characteristic stem-cell morphology," some might not measure up. Even NIH admits that not all the colonies display stem-cell "markers," molecules dangling from the cell surface that act as little "I am a stem cell" signs. Of the 19 lines at Goteborg University in Sweden--the most NIH knows of--15 have not yet demonstrated pluripotency. Four, still frozen, haven't been analyzed. Of the 10 at Reliance Life Sciences and the National Centre for Biological Sciences in India, none are definitely pluripotent stem cells. And India prohibits the export of biological materials, meaning the colonies are probably useless to American researchers unless they decamp to Calcutta.
That leaves only a couple of dozen identifiably pluripotent colonies. "Ours are available with proper arrangements," says Dr. Rafael Beyar, dean of Israel's Technion, which has four colonies. The two lines at the University of California, San Francisco, are also good to go, says Dr. Sue Shafer. Are there enough? Stem cells are typically held in suspended animation--alive but not reproducing. To meet the expected demand, the cells would have to start replicating, fast. "But if you do that, they can differentiate or develop chromosomal abnormalities," says Shafer. That would limit the supply even more--suggesting that "64" might not be 64 after all.